<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <div id="app"></div>
    <script type="text/javascript" src="../js/react.development.js"></script>
    <script type="text/javascript" src="../js/react-dom.development.js"></script>
    <script type="text/javascript" src="../js/babel.min.js"></script>
    <script type="text/babel">
    class Demo extends React.Component {
        // 创建一个存储节点的容器
        myRef = React.createRef();
        showData = () => {
            alert(this.input1.value);
        }

        render() {
            return (
                <div>
                   <input ref={c => {this.input1 = c; console.log('执行了', c)}} type="text" placeholder="点击提示数据" />&nbsp; 
                    <button onClick={this.showData}>点击提示左侧数据</button>
                    <br/>
                </div>
            )
        }
    }
    ReactDOM.render(<Demo />, document.getElementById('app'))
    </script>

</body>
</html>